When you work in a company, you will need to talk to someone else. How to say is you must give respect to the speaker (s) and use a suitable speech and speaking clearly. Not keen on the others.
When you work in a company, you have to talk with others. How good is saying you have to give respect to those who speak and use words appropriate to speak and speak clearly. Do not speak negatively about others.
When you work for a company you will need to talk with others. How to say good is that you must respect the speaker and the phrase with appropriate speech and say ให้ชั clearly, not speaking negatively by others.